Knife-edge pivot for scales



Feb. 2,1926. 1,571,265

c. H. HARTMAN KNIFE EDGE PIVOT FOR SCALES Filed Jfme 19. 1922 Clan! esjljiartman Patented Feb. 2, 1926.

UNITED STATES PATENT OFFICE.

CHARLES TI. HARTMAN, 0F LOUISVILLE, KENTUCKY, ASSIGNOR TO WALTER F. QTIMPSON, OF LOUISVILLE, KENTUCKY.

KNIFE-EDGE PIVOT FOB SCALES.

Application filed June 19, 1922.

To all 2.0 7mm it may concern Be it known that I, CHARLES H. I-IAirruAN, a citizen of the United States of America, residing at Louisville, in the county of Jefferson and State of Kentucky, have invented certain new and useful Improvements in Knife-Edge Pivots for Scales, of which the following is a specification, reference being had therein to the accompanying drawings.

The invention relates to the manufacture of knife-edge pivot unit for scales and consists in the novel construction as hereinafter set forth.

In the drawings:

Figure 1 is a perspective view of the pivot;

Figures 2 and 3 are perspective views of the knife-edge portion and the body portion detached Figure 4 is a cross-section showing the knife-edge portion and body portion in interlocked engagement; and

Figure 5 is a similar view showing these parts in locked engagement.

Figure 6 is a view similar to Fig. 5 showing a modified construction.

In the manufacture of knife-edge pivots one method is to take bar stock and to grind or otherwise fashion the end portions thereof into a V-shape, leaving the central portion of full cross-section. This results in forming at the points of change in cross section lines of weakness. Also, there is consider able waste of stock due to the cutting away of the ends. WVith my improved construction I combine a bar of uniform V-shaped cross section with a body of lesser length having a V-shaped channel therein for re ceiving the central portion of said portion and being secured thereto.

As shown. A is the bar of uniform crosssection throughout its length and B is the body member which, as shown, is of circular cross section and of a length less than that of the bar A. The body portion B has formed therein a V-shaped longitudinally extending channel C adapted to receive the bar A. As shown, the apex of this V-shaped channel is the axis of the cylindrical body Serial No. 569,317.

and the outer edge of the bar, when placed in the channel, forms a complementary segment of the cylinder. The bar is then securely attached to the body by any suitable means, which, as specifically shown, consists in chamfering the edges of the bar at D and peening over the adjacent edges of the body as at E. This will produce an effectual mechanical lock and as the bar A is not otherwise attached to the body, there will be no line of weakness, as is the 0 case where the V portions and cylindrical portions are integral. It will be understood that the V-shaped channel is formed of a material of suitable hardness, such as hardened steel, but that the body may be made of relatively soft material.

In the modified construction shown in Fig.

6, the bar A is secured by cutting away either the edge portion of the bar or the body to form a recess, and filling in this re- 7 cess with solder.

What I claim as my invention is:

1. An article of manufacture consisting of a knife-edge bearing unit for scales comprising a bar of uniform V-shaped cross section, a body of a different cross-section and lesser length than the bar engaging the central portion having a V-shaped channel for receiving the central portion of said bar, and means for rigidly locking said bar in 30 said recess.

2. An article of manufacture consisting of a knife-edge pivot unit for scales com prising a bar of uniform V-shaped crosssection, a body of cylindrical cross-section 35 and of a length less than that of the bar, being provided with a V-shaped channel for receiving and fitting the cross-section of the bar, and means for rigidly securing said bar in said channel.

3. An article of manufacture consisting of a knifeedge pivot unit for scales comprising a bar of uniform V-shaped crosssection, a body of a different cross section and lesser length provided with a \/shaped channel therein for receiving and fitting said bar, a portion of the body at the edge of said channel being deflected to interlock with said bar and to rigidly retain the same in said channel.

4. Anarticl'e of manufacture consisting of a knife-edge pivot unit for scales comprising a bar of uniform V-shaped cross-section, and a body of a different cross-section and lesser length of the bar having a V-shaped channel therein for receiving said bar, the central portion of the outer edge; of said bar being ehainfered and said body portion be- 10 ing peened over to interlock with said chamfer and to rigidly lock said parts together. In testimony whereof I aflix my signature.

CHARLES H. HA'RTMAN. 

